Depending on the processed material from each drill must be properly sharpened. To verify the correct angle will help a specially prepared square plate of copper or aluminium with a thickness of 1 mm.
To become operational protractor enough to cut it cut, as shown in the picture: a large cutout at an angle of 120 degrees, the other half is 60 degrees and the surviving corner of a square is 90.
Recommend to read
URAL “THREE-TON”
Autumn the evacuation of 1941, which resulted in the defense enterprises of the capital was transferred to the East of the country, has transformed a provincial town, which was the...
SOVIET LIGHT TANK T-30
SOVIET LIGHT TANK T-30. Scale model 1:25. Floating tank T-40 serially produced in the USSR since 1940 and was intended to replace the T-37A and T-38. As its predecessors, its design...